Flexible, vertically-adjustable dam



April 19, 1966 J. J. E. MESNAGER 3,246,474

FLEXIBLE, VERTICALLY-ADJUSTABLE DAM Filed Oct. 19. 1961 s Sheets-Sheet 1 April 1966 J. J. E. MESNAGER 3,246,474

FLEXI BLE VERTI CALLY-ADJUS TABLE DAM Filed Oct. 19, 1961 3 Sheets-Sheet 2 Fig". 5.

Flg] [f 52 C2 INVENTOR JHCGIUES JEAN ENILEMES/WE? WWW M A ril 19, 1966 J. J. E. MESNAGER 3,246,474

FLEXIBLE, VERTICALLY-ADJUSTABLE DAM Filed 00M 19, 1961 3 Sheets-Sheet 5 I* 8 B c IN VEN TO K mam/E5 JEAN EMILE MESNHGER {B7 MAM/d W United States Patent M 3,246,474 FLEXIBLE, VERTICALLY-ADJUSTABLE DAM Jacques Jean Emile Mesnager, 182 Rue de Rivoli, Paris, France Filed Oct. 19, 1961, Ser. No. 146,0?6 Claims priority, application France, Get. 29, 1960, 841,681, Patent 1,2773% 3 Claims. (Cl. til-30) The essential object of this invention is to provide a flexible, vertically adjustable dam or weir for rivers or canals, which consists essentially of a flexible tube secured transversely on a sill constructed on the bottom of the river or canal bed along at least one generatrix extending throughout the tube length, said tube being inflated wth a gaseous or liquid fluid exerting a pressure greater than that exerted by the upstream liquid at all levels.

By varying the pressure of the inner or inflation fluid the tube shape may be varied from a complete flat condition when this pressure approximates upstream outer pressures, to nearly circular shapes barring the bed section when the inner pressure exceeds to a sufficient degree the upstream pressures at each level.

The use of a gaseous or liquid fluid is advantageous in that it protects the darn from frost while enabling the dam to become safely flat irrespective of the downstream water level.

The tube is secured on the sill along a generatrix so that the flexible wall of the tube is preserved integrally and may thus be held against movement by external means without necessitating any perforation of its wall.

The features and advantages of this invention will appear more clearly as the following description proceeds with reference to the accompanying drawing illustrating diagrammatically by way of example typical embodiments of the flexible dam of this invention. In the drawing:

FIGURE 1 is a cross section showing the flexible inflated dam-forming tube and the means for securing one generatrix of this tube on the sill, these means being magnified to a substantial extent for facilitating the understanding;

FIG. 2 is a longitudinal cross-sectional view of the inflated dam-forming tube, the section being taken transversely of the river bed;

FIG. 3 is a transverse sectional View of the inflated dam-forming tube;

I FIG. 4 is a plan view of the dam-forming tube, showing in dot and dash lines the position of the downstream generatrix of the dam when the tube is deflated;

FIG. 5 is a view, similar to FIG. 2, showing a damforming inflatable tube embodying the invention and in which the tube ends are fixed to the river banks at points shifted downstream with respect to the fixation of the tube on the flooror sill;

FIGS. 6 and 7, are views corresponding respectively to FIGS. 3 and 4, of the arrangement shown in FIG. 5;

FIG. 8 is a longitudinal sectional view of a damforming inflatable tube, showing an embodiment in which the ends of the tube have screening walls associated therewith;

FIG. 9 is a plan view corresponding to FIG. 8;

FIG. 10 is a transverse sectional view of the arrangement shown in FIG. 8; and

FIG. 11 is a longitudinal sectional View, corresponding to FIG. 10, illustrating a modification.

As illustrated in FIG. 1, the generatrix along which the flexible tube 2 is secured on the sill 1 comprises an inner, bead-forming cord 3. The fold containing this cord 3 is secured on the sill 1 by clamping same by means of jaws 4 disposed at spaced intervals across the sill,

, 3,246,474 Patented Apr. 19, 1956 each jaw being secured by an anchor bolt 5 provided with an adjustment nut 6.

In the structure illustrated in FIG. 2 the bed acrosss which the flexible dam is to be mounted has a trapezoidal transverse contour S B, C and S wherein S and S are the opposite bank points between which a dam is to be erected. The surface of the flexible tube 2-shown in its inflated conditionis shaped to comprise essentially a cylindrical portion having two opposite conical end extensions having their vertices secured at S and S the generatrix along which the tube is secured on the sill consisting of a broken line S B C and S as shown in FIG. 4, this line being slightly bent in the upstream direction, that is, in a direction opposite to that shown by the arrow 1. When this flexible tube 2 is flat, that is, before its inflation, it extends along the sill 1 in the direction of the stream in a position 2a (FIG. 4) following the contour S B C and S which is bent downstream. When the tube is inflated, it lies in position 2 as shown in FIGS. 2 and 4. FIG. 3 illustrates more particularly the main vertical cross-section 2 of the tube which is taken in the plane of the canal axis. The broken line S B C S and the straight line S B, C, S show, notably in FIG. 4, respectively, the downstream contour and the top line of the inflated tube. As a consequence of the cylindro-conical developed configuration of the tube and since the length S B, C, S is smaller than the length of the anchored generatrix S B C S two folds are formed on the top of the tube, substantially at the joint between the cylindrical portion and the conical portions of the tube. When the inner pressure of the tube is varied the. cross-sectional contours of the tube vary accordingly both in the conical portions and in the cylindrical orapproximately cylindrical portion, the straight cross-sections of the conical portions being approximately homothetic to that of the adjacent cylindrical portion, their similarity being centered on. the vertices of the conical portions.

Thus, the tube may undergo a deformation ranging from maximum inflation to complete flattening on. the sill, nearly without folds, with a wall consisting of a nonextensible diaphragm.

Another typical embodiment of the invention, illustrated in FIGS. 5 to 7 and designated by the same reference symbols primed, as used in- FIGS. 4 to 6, consists in displacing the vertices of the external conical portions in relation to the anchored generatrix S B C 5., so that the upper generatrix of the inflated tu-be S B, C, 5,, (which. in this case has the form of a horizontal trapezium) has substantially the same development as in position S B C 8.; after the deflated tube has been flattened on the canal cross-section also of trapezoidal configuration.

With this arrangement, the folds formed on the upstream side of the inflated tube where the conical end portions are connected to the central cylindrical portion maybe eliminated, and the only folds left are vertical folds B, C on the downstream face. These folds will not cause leakages in the upstream to downstream direction as in the preceding embodiment wherein the upper generatrix of the conical portions of the dam is substantially co-extensive with that of the cylindrical portion.

In the alternate embodiments illustrated in FIGS. 8 to 10 of the drawing the river or canal banks are completed by overhanging screen-forming walls G, H so that the section S B, C, S CB to be closed constitutes the meridian of a surface of revolution comprising a cylinder closed at either ends by two conical portions coaxial with this cylinder. By virtue of this light masonry work the tube can be given substantially the shape of the surface of revolution described hereinabove in order to minimize the folds likely to be formed in the tube during its inflation.

Instead of forming the tube ends with conical portions, i

any other suitable configuration may be contemplated for these end portions, for example more or less rounded shapes coaxial with the cylindrical central portion. In this case the desired concave contour must be given to the lower overhanging face of each screen-forming wall G, H, as shown in FIG. 11.

Instead of securing the tube on a sill constructed on the bottom B C of the river or canal bed, this tube can be secured under a beam constructed above the bed, and the tube may if desired be disposed partly beneath, partly above this beam; this arrangement is advantageous for removing the gravel accumulating on the upstream side of the tube on the river or canal bed.

Although the present invention has been described in conjunction with preferred embodiments, it is to be understood that modifications and variations may be resorted to without departing from the spirit and scope of the invention, as those skilled in the art will readily understand. Such modifications and variations are considered to be within the purview and scope of the invention and appended claims.

What I claim is: Y

1. A flexible dam for retaining water comprising a flexible wall defining a generally horizontally extending inflated collapsible tube, having longitudinal generatrices, disposed longitudinally across the channel to be dammed between the banks, means securing said wall to a slab laid on the channel bed across the channel, said means being disposed along a generatrix of the tube at the lower portion of the tube, said tube comprising a central portion of substantially uniform cross-sectional area transversely thereof and end portions, each end portion extending from an end of said central portion, said end portions having a gradually and uniformly decreasing transverse cross-sectional area providing a tapered configuration closing said tube at both ends, and defining cones each on its underside terminating at a vertex portion being secured to the bank in the middle of the height of the central portion of the dam to limit laterally the channel to be dammed, means for inflating said tube at a pressure corresponding with the desired effective height of the tube above said slab, and a pair of screen forming walls each extending from a respective channel bank and each having an edge substantially conforming to and overhanging one of said end portions and its vertex portion, said screen-forming walls extending upwardly from said end portions and bank at least level with the desired effective height of the central portion of said tube.

2. An inflatable flexible dam for retaining water in a stream bed having a flat bed base and two upwardly sloping banks each extending longitudinally of a respective side of said flat bed base, said dam comprising an elongated, hollow, flexible central cylindrical portion of uniform cross-section throughout its length and having a flattened bottom extending transversely of the base of the stream bed, and two hollow, conical, flexible end portions defining continuations of said central portion and each extending transversely of a respective upwardly sloping bank; the transverse cross section of each said conical end portions being substantially homothetic with that of said central cylindrical portion and providing flattened bottoms therefor, and continually diminishing toward the vertex of the respective conical portion; clamping means for anchoring said dam on said bed, said clamping means extending straight at least along the upstream lower edge of the flattened bottoms of said central portion and continuing upwardly along said sloping banks on the upcal end portions, and inclining downstream of the up stream lower edge of said central portion from the ends of the latter to the vertices' of said conical end portions; the upper generatrix of said dam, extending substantially rectilinearly between said vertices, its length remaining constant in both the inflated and ground engaging flattened conditions of said dam and,- in the inflated condition of said dam, being nearer to the edge opposite the fastened edge thereof than to the fastened edge; and means for inflating said hollow flexible central cylindrical portion and said flexible end portions at a pressure corresponding to the desired height of said dam above said bed.

3. An inflatable flexible dam for retaining water in a stream bed having a flat bed base and two upwardly sloping banks each extending longitudinally of a respective side of said flat bed base, said darn comprising an elongated, hollow, flexible central cylindrical portion of uniform cross-section throughout its length and having a flattened bottom extending transversely of the base of the stream bed, and two hollow, conical, flexible end portions defining continuations of said central portion and each extending transversely of a respective upwardly sloping bank; the transverse cross section of each said conical end portions being substantially homothetic with that of said central cylindrical portions and providing flattened bottoms thereof, and continually diminishing toward the vertex of the respective conical portion; clamping means for anchoring said dam on said bed, said clamping means extending straight at least along the upstream lower edges of the flattened bottoms of said central portion and continuing upwardly along said sloping banks on the upstream lower edges of the flattened bottoms of said conical end portions, and inclining downstream of the upstream lower edge of said central portion from the ends of the latter to the vertices of said conical end portions; the vertices of said conical end portions being at a common level at least as high as the midpoint of the inflated height of said central cylindrical portion; the length of the upper generatrix of said dam, remaining constant in both the inflated and ground engaging flattened conditions of said dam and, in the inflated condition of said dam, being nearer to the edge opposite the fastened edge thereof than to the fastened edge; and means for inflating said dam at a pressure corresponding to the desired height of said hollow flexible central cylindrical portion and said flexible end portions above said darn.

References Cited by the Examiner UNITED STATES PATENTS 1,713,605 5/1929 Jones 61-29 1,852,268 4/1932 Schmidt 6l29 2,609,666 9/1952 Mesnager 6l'30 3,067,712 12/1962 Doerpinghaus 61-5 X FOREIGN PATENTS 1,064,129 12/1953 France.

145,007 7/1920 Great Britain.

33,366 10/1921 Norway.

OTHER REFERENCES Construction Methods and Equipment (publication), August 1959, p. 216.

Modern Plastics, page 83, September 1961.

EARL J. Vi/INTER, Primary Examiner.

JACOB L. NACKENOFF, WILLIAM I. MUSI-IAKE,

Examiners. T. W. FLYNN, Assistant Examiner. 

3. AN INFLATABLE FLEXIBLE DAM FOR RETAINING WATER IN A STREAM BED HAVING A FLAT BED BASE AND TWO UPWARDLY SLOPING BANKS EACH EXTENDING LONGITUDINALLY OF A RESPECTIVE SIDE OF SAID FLAT BED BASE, SAID DAM COMPRISING AN ELONGATED, HOLLOW, FLEXIBLE CENTRAL CYLINDRICAL PORTION OF UNIFORM CROSS-SECTION THROUGHOUT ITS LENGTH AND HAVING A FLATTENED BOTTOM EXTENDING TRANSVERSELY OF THE BASE OF THE STREAM BED, AND TWO HOLLOW, CONICAL, FLEXIBLE END PORTIONS DEFINING CONTINUATIONS OF SAID CENTRAL PORTION AND EACH EXTENDING TRANSVERSELY OF A RESPECTIVE UPWARDLY SLOPING BANK; THE TRANSVERSE CROSS SECTION OF EACH SAID CONICAL END PORTIONS BEING SUBSTANTIALLY HOMOTHETIC WITH THAT OF SAID CENTRAL CYLINDRICAL PORTIONS AND PROVIDING FLATTENED BOTTOMS THEREOF, AND CONTINUALLY DIMINISHING TOWARD THE VERTEX OF THE RESPECTIVE CONICAL PORTION; CLAMPING MEANS FOR ANCHORING SAID DAM ON SAID BED, SAID CLAMPING MEANS EXTENDING STRAIGHT AT LEAST ALONG THE UPSTREAM LOWER EDGES OF THE FLATTENED BOTTOMS OF SAID CENTRAL PORTION AND CONTINUING UPWARDLY ALONG SAID SLOPING BANKS ON THE UPSTREAM LOWER EDGES OF THE FLATTENED BOTTOMS OF SAID CONICAL END PORTIONS, AND INCLINING DOWNSTREAM OF THE UP- 